1. 阿里云云数据库PolarDB：
它是一个与 MySQL、PostgreSQL 和 Oracle 兼容的云原生关系数据库。云数据库架构在单个集群中支持 5000 台物理机。它专为需要快速性能、高并发和自动扩展的业务关键型数据库应用程序而设计。
2.快板图：
它是一个高性能、持久的 RDF 存储，额外支持 Graph DBMS。它作为文档存储运行，旨在以 JSON-LD 格式存储、检索和管理面向文档的信息。 AllegroGraph 的第一个版本于 2004 年发布。阿里云PolarDB版和AllegroGraph的区别：
| S.NO. | Alibaba Cloud ApsaraDB for PolarDB | ALLEGROGRAPH |
|---|---|---|
| 1. | It was developed by Alibaba in August 2013. | It was developed by Franz Inc. in 2004. |
| 2. | It is a cloud-native relational database compatible with MySQL, PostgreSQL, and Oracle. | It is a high performance, persistent RDF store with additional support for Graph DBMS. |
| 3. | In Alibaba Cloud ApsaraDB for PolarDB there are hosted server operating systems. | Server operating systems for AllegroGraph are Linux, OS X and Windows. |
| 4. | The license of Alibaba Cloud ApsaraDB for PolarDB is commercial. | The license of AllegroGraph is also commercial. |
| 5. | It supports XML Format. | It does not support XML Format. |
| 6. | It supports the Server-side scripting | It support the Server-side scripting with JavaScript or Common Lisp. |
| 7. | There is only one partitioning method – Sharding. | The partitioning can be done with Federation. |
| 8. | It supports SQL query language. | It uses SPARQL as query language. |
| 9. | It supports replication methods. | It support two replication methods : Master-Slave Replication and Multi-Master Replication. |
| 10. | ApsaraDB for PolarDB provides the concept of Referential Integrity. Hence, there are Foreign Keys. | AllegroGraph does not provide the concept of Referential Integrity. Hence, no Foreign Keys. |
| 11. | It supports in-memory capabilities. | It does not support in-memory capabilities. |
| 12. | It does not offer any API for user-defined Map/Reduce methods. | It also does not offer any API for user-defined Map/Reduce methods. |
| 13. | It is available as a cloud service. | It is not available as a cloud service. |
| 14. | Programming languages supported are Java and Python. | Programming languages supported are C#, Clojure, Java, Lisp, Perl, Python, Ruby and Scala. |